What happens is sand and dirt tend to get under the rubber insulators at the mounting brackets and they scrub through the finish of the aluminum pipe over time, until the pipe leaks. Originally, most were replacing the entire rear piping assembly, Nissan P/N 92470-9CA0A, which requires jacking the right side of the body off of the frame in order to install the lines. Then, Nissan shipped the dealers pipe repair kits so they could just repair the section of pipe and not have to replace the whole line assembly, which is a lot easier and less costly, obviously. The Dorman 800-600 AC Line repair kit is one such kit that can do this (it works on both aluminum heater or A/C lines); here's a link to a YouTube video showing it in action:
https://www.youtube.com/watch?v=h1O3w_I97Ak
A temporary fix can be made by cutting the line at the leak and install rubber heater hose and clamps on the line to join the two end of the pipe, but because this is close to the exhaust pipe, it should not be used as a permanent fix.
As far as the whole line, it is part code "92460QA" in the part diagram linked below:
https://www.nissanpartsdeal.com/parts-l ... m=276_A002